Dark streaks known as recurring slope lineae (RSL) grow up to a few hundred meters in length and are formed by briny liquid water. These streaks lengthen and get darker in the warmer months and fade away in the cooler parts of the year. For years it has been hypothesized that they were created by water but there was no evidence until now. Spectrometer observations of the RSL show signatures of hydrated salts which confirm the hypothesis.

“We found the hydrated salts only when the seasonal features were widest, which suggests that either the dark streaks themselves or a process that forms them is the source of the hydration. In either case, the detection of hydrated salts on these slopes means that water plays a vital role in the formation of these streaks,” said Lujendra Ojha of the Georgia Institute of Technology, lead author of a report published in Nature Geoscience.

Comments (3):

apparently it's beads of water condensed and frozen out of the air, later warmed up and melted to form tiny saltwater threads. just a little leftover from the times when oceans covered a fifth of mars. not very useful to life or a mars colony.

Mars is, to this day, a riddle wrapped in a mystery inside an enigma. We are still in our infancy understanding the universe... even those bodies closest to us leave us dazzled.

Recently, there was an image sent back from MSL Curiosity of something that looked crab-like but... it was immediately dismissed as pareidolia. If that same image had been from our world, it would have never been called, a 'rock'.

We won't really know if we don't go. Sidenote: NASA has been promising a manned mission since the end of the Apollo program but each time we got close to their officially released dates, they kicked it back over the horizon.

a manned mission to mars is pretty much pointless at this time. the rovers and fly-bys have given us so much information that putting boots on mars other than to start a colony would be a giant waste of money and resources.

btw the crab-thing was exactly that... a rock... just like every other non-earth exotic has proved to be so far.